Recently named the world's best racehorse, Arrogate has won the world's richest race, the $12 million Pegasus World Cup Invitational in Florida while California Chrome has ended his career on a disappointing note.

Hall of Fame jockey Mike Smith piloted four-year-old Bob Baffert-trained Arrogate into the lead with a dominant run around the final turn and he pulled away down the straight to win by 3-1/2 lengths.

Arrogate covered the 1810 metres at Gulfstream Park on Saturday (Sunday AEDT) in an unofficial time of 1 minute, 47.61 seconds to secure the $7 million first prize.

Shaman Ghost finished second, with Neolithic battling home third.

California Chrome, faded in the straight in the final race of a stand-out career which included victories at the 2014 Kentucky Derby and Preakness Stakes and the 2016 Dubai World Cup.

It was a disappointing climax to a much anticipated repeat showdown between Arrogate and California Chrome, who had placed one-two after a thrilling finish to the Breeders' Cup Classic three months ago at Santa Anita in California.

"Another incredible performance," Smith told NBC Sports.

"I was able to use the first turn to our advantage, stayed on the rail ... it was just a matter of getting the trip.

"I looked halfway down the backside and I saw (jockey) Victor (Espinoza) having the nudge on Chrome a little. He had me right where he wanted me but Chrome just didn't fire his race today at all.

"Believe me, that's not the California Chrome I know. He would have been on top of me. I was able to tip out and he (Arrogate) was gone after that. I don't mean any disrespect to the other good horses, but he got to gear down the last 100 yards."

California Chrome, North America's all-time leading money earner and the Horse of the Year in 2014 and 2016, ended his stellar career placed ninth in a 12-runner field, his worst ever finish in 27 starts.

Last week Arrogate beat Calfiornia Chrome in the World's Best Racehorse awards in which Australian champion Winx was named the the best on turf.